I disagree I think she did make a choice, but marriage in Austen's time wasn't about love, it was about wealth and connection. Charlotte's choice is difficult for Lizzy to understand because she finds it crass and would rather be single than marry the wrong man, the fact that Darcy is rich, show's that Austen was trying demonstrate that class and connections were bounderies that could be broken for love...the fact that she refuses him outright at first, shows that she did make a choice, she wouldn't marry a man just for his money...that she later falls in love with him is what changes her mind. Also fighting against Lady Catherine's objections further shows that Austen was trying to show that those walls could be broken down for love, despite what society and decorum may think.
